Although there exists a relationship between alcohol consumption and alcoholic liver disease at both the aggregate and individual levels, it is also well established that less than one-third of alcoholics or heavy drinkers develop serious alcohol-related liver damage. A number of factors have been proposed to account for this susceptibility. Evidence supporting the direct dose-response relationship and the role of genetic and environmental factors in influencing vulnerability are reviewed. To date, no consistent evidence attests to the significance of any one factor in the susceptibility to developing alcoholic liver disease.